diff --git a/hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/6_1_0/3714-improve-chained-search-performance.yaml b/hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/6_1_0/3714-improve-chained-search-performance.yaml
new file mode 100644
index 00000000000..18e792d33e6
--- /dev/null
+++ b/hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/6_1_0/3714-improve-chained-search-performance.yaml
@@ -0,0 +1,4 @@
+type: perf
+issue: 3714
+jira: SMILE-4484
+title: "Chained searches have been sped up for configurations where the `Index Contained Resources` feature is enabled."
diff --git a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/search/builder/QueryStack.java b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/search/builder/QueryStack.java
index e44556518be..4c8b1363b06 100644
--- a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/search/builder/QueryStack.java
+++ b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/search/builder/QueryStack.java
@@ -933,7 +933,7 @@ public class QueryStack {
 		EnumSet<PredicateBuilderTypeEnum> cachedReusePredicateBuilderTypes = EnumSet.copyOf(myReusePredicateBuilderTypes);
 		myReusePredicateBuilderTypes.clear();
 
-		UnionQuery union = new UnionQuery(SetOperationQuery.Type.UNION);
+		UnionQuery union = new UnionQuery(SetOperationQuery.Type.UNION_ALL);
 
 		ReferenceChainExtractor chainExtractor = new ReferenceChainExtractor();
 		chainExtractor.deriveChains(theResourceName, theSearchParam, theList);